Precast Concrete Wall Panel Thickness 2

[StructuralEngGuy]

Hello All,

I have a steel framed tower that will be clad with precast concrete panels. The floor to floor height is 11'-8" on the tower. The maximum width of the panel is about 17' per the architectural elevations. I'm planning to use 5" panels with 3/4" reveals. The panel design is delegated to the contractor. Is there any minimum thickness requirement that I should be aware of for the panel size I plan to use? I think the 5" thickness is plenty for the floor to floor height span, but I wonder if it would suffice during erection?

Thanks in advance.

 

[JAE]

Call a local panel precaster and ask.

5" sounds OK to me = L/50 is a starting point for tilt-up panels.

At 17 feet that gives you 4" as a min.

 

[concretemasonry]

If the pre-cast subcontractor/supplier casts in a plant and does the actual erection, he would probably want to be responsible for the design for erection structural design (which is different from normal loadings), otherwise there can be complex problems if they are architectural and have to be replaced.

If they are site cast panels because of the transportation and logistics, that leaves the responsibility on the contractor since swinging some thing that size from horizontal to vertical can be problematic.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[JAE]

Well he still needs to know ahead of time how heavy they are to design the supporting structure.

 

[spats]

What is the total height/length of the panel? What matters for erection is the total height of each panel, not the floor-to-floor height. If you are stacking panels, the best way to set the upper panels is to edge lift them, rather than having to face lift, then switch to edge inserts. This may require the panels to be thicker. For mild reinforced panels you can get an idea of the thickness required for lifting by downloading a copy of Dayton Superior's Tilt-Up Handbook at daytonsuperior.com.

If the panels are to be shop fabricated and shipped to the jobsite, you need to limit the width to 12' so they'll fit on a truck bed.

 

[StructuralEngGuy]

Spats, the total size of the largest panel is 17'x11'-8".

 

[hokie66]

The architect needs to know the panel dimensions, including the haunch details, before proceeding with his floor planning. So I don't think there is any option but to coordinate with a precaster.

 

[Brad805]

I have seen a lot 4" thick non-load bearing panels like these. I agree with the others you need to talk to the contractor to see if these are going to be cast on site or precast.

Brad

 

[csd72]

A few comments:

The H/50 is a good rule of thumb for most panels and is used as a minimum rule in a number of countries.

Be careful with cantilevers as I have actually seen panels vibrating and swaying in the wind.

I have encountered problems with obtaining suitable fixings for thin panels 4.5 inches and less so this may also be a problem for this.

There are so many variables so you definately need to get the precaster involved.